1. Field of the Invention
The present invention relates to a silphenylene-containing photocurable composition, a pattern formation method that uses the composition, and an optical semiconductor element obtained using the method. The invention relates particularly to a silphenylene-containing photocurable composition which, due to its superior properties of transparency, light resistance and heat resistance, is useful in optical devices typified by light-emitting elements such as light-emitting diodes (LED), light-receiving elements such as photodiodes, optical sensors and CMOS image sensors, and optical transmission devices such as optical waveguides, as well as a pattern formation method that uses the silphenylene-containing photocurable composition, and an optical semiconductor element obtained using the method.
2. Description of the Prior Art
Epoxy resins have typically been used as the encapsulating protective material within various optical devices typified by LEDs and CMOS image sensors. Among such resins, a large number of epoxy-modified silicone resins have been used due to their high levels of transparency and light resistance, and resins in which alicyclic epoxy groups have been introduced into a silphenylene backbone also exist (see Patent Document 1). However, these resins are not capable of undergoing microfabrication in the order of 10 μm. Nowadays, many types of optical devices require microfabrication. When this type of microfabrication is required, resist materials typified by epoxy resin-based materials have often been used, but these resist materials tend to have inadequate light resistance, meaning although there may be no problems with devices of low light intensity, devices that use a stronger light intensity have tended to suffer from problems such as gas emission and discoloration.
[Patent Document 1] EP 0 447 926 A2